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Wandering Soulstar

Threshold for LI Growth

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Hi All,

I have a question in regards to uploaded mesh and the LI said items require. It seems to me that there must be a threshold, either in triangles, or size of the uploaded mesh where the cost goes up noticeably. What I mean is explained by the following scenario. Before I go into it, I am using Mesh Studio to create DAE files from inworld prim builds. Please no comments about using Blender, etc, I know them and just do not have time atm to learn this. In any case I doubt that this is the issue .. so the scenario:

  • 23 prim linkset(basically a wall and window with frame, and is 6m wide by 5m high. When I take the created DAE file to upload it shows at high 156 triangles/312 vertices. Use the same DAE for medium, and then auto-generated for the other two (14/26 and 10/14 respectively). This gives me a mesh of 0.7LI.
  • Now double the original and create a linkset with 46 prims, 13m wide and still 5m high. Going to upload the DAE file shows 316 triangles and 632 vertices for hig, as above use the same for medium and auto-generated for the other two (23/43, 14/26). so far everything is 2x the original .. until we get to the LI, which is 3.9, 5.57x the original, or almost 2.8x what it would be just using the earlier mesh twice in-world.

So what this is showing me is that there is some threshold that changes to way the LI is calculated, and I suspect it it the size of the original build. So my question is, what is that threshold, i.e. when is it better for me to break things up into smaller pieces.

 

Thanks in advance,

Wanda

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Yes, size matters. The larger your mesh is, the more LODs are going to be ignored by the LI calculation. The radius of the bounding box (think of a sphere encompassing the mesh) is what determines which of the lower LODs is being dropped.

If said radius is larger than 5.43 meters, the lowest LOD will be ignored.
If said radius is larger than 10.86 meters, the low, and lowest LOD will be ignored.
If said radius is larger than 43.44 meters, othe lowest, low, and medium LOD will be ignored.

The formula to get the radius is sqrt(x*x + y*y + z*z) / 2

Also, it's always a good idea to keep larger meshes as lowpoly as possible, and add window frames, and any detail as a separate mesh object.

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@Chic Aeon .. to be clear I am not uploading a linkset, as I stated I am using Mesh Studio to create the DAE file, and that is what it is for, turning prim linkest into reasonably good DAEs. Appreciate the link to the limits, but was looking for thresholds where the upload wieght's change.

@arton Rotaru This helps greatly. Just to be certain I understand it, past the 5.43m radius the lowest LOD will be replaced by the low, past 10.86m the lowest and low will be replaced by the medium, and then past the 43.44m radius the only LOD being used is the highest. That then would explain what I am seeing, the double size has passed the 10.86m radius and so the medium LOD is being applied to all.

Thanks to both for your quick responses!

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For an object of the size of, let's say, 13 x 0.5 x 5.0 the BB radius would be 6.97 meters. So the lowest LOD won't make it into the LI calculation. You could put the Low LOD in the slot of the Lowest LOD as well, and the LI will remain the same.

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